commit 39853bbc497d4ca19c553a620afdc459e81d67ce
author Jan Kiszka <jan.kiszka@siemens.com> Thu May 17 10:32:36 2012 -0300
committer Avi Kivity <avi@redhat.com> Mon May 21 19:22:50 2012 +0300
tree ec743b6b3c5411d29e493af3b6fe03fcc63bb036
parent e7b2030862f63ee02331940b9f1742cd025c1908

kvm: Introduce kvm_irqchip_add/remove_irqfd

Add services to associate an eventfd file descriptor as input with an
IRQ line as output. Such a line can be an input pin of an in-kernel
irqchip or a virtual line returned by kvm_irqchip_add_route.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

kvm-all.c

diff --git a/kvm-all.c b/kvm-all.c
index e96f092..489ee53 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -1108,6 +1108,21 @@
     return virq;
 }
 
+static int kvm_irqchip_assign_irqfd(KVMState *s, int fd, int virq, bool assign)
+{
+    struct kvm_irqfd irqfd = {
+        .fd = fd,
+        .gsi = virq,
+        .flags = assign ? 0 : KVM_IRQFD_FLAG_DEASSIGN,
+    };
+
+    if (!kvm_irqchip_in_kernel()) {
+        return -ENOSYS;
+    }
+
+    return kvm_vm_ioctl(s, KVM_IRQFD, &irqfd);
+}
+
 #else /* !KVM_CAP_IRQ_ROUTING */
 
 static void kvm_init_irq_routing(KVMState *s)
@@ -1123,8 +1138,23 @@
 {
     abort();
 }
+
+static int kvm_irqchip_assign_irqfd(KVMState *s, int fd, int virq, bool assign)
+{
+    abort();
+}
 #endif /* !KVM_CAP_IRQ_ROUTING */
 
+int kvm_irqchip_add_irqfd(KVMState *s, int fd, int virq)
+{
+    return kvm_irqchip_assign_irqfd(s, fd, virq, true);
+}
+
+int kvm_irqchip_remove_irqfd(KVMState *s, int fd, int virq)
+{
+    return kvm_irqchip_assign_irqfd(s, fd, virq, false);
+}
+
 static int kvm_irqchip_create(KVMState *s)
 {
     QemuOptsList *list = qemu_find_opts("machine");

kvm-stub.c

diff --git a/kvm-stub.c b/kvm-stub.c
index ec351d9..b4cf03f 100644
--- a/kvm-stub.c
+++ b/kvm-stub.c
@@ -140,3 +140,13 @@
 void kvm_irqchip_release_virq(KVMState *s, int virq)
 {
 }
+
+int kvm_irqchip_add_irqfd(KVMState *s, int fd, int virq)
+{
+    return -ENOSYS;
+}
+
+int kvm_irqchip_remove_irqfd(KVMState *s, int fd, int virq)
+{
+    return -ENOSYS;
+}

kvm.h

diff --git a/kvm.h b/kvm.h
index f0d0c53..9c7b0ea 100644
--- a/kvm.h
+++ b/kvm.h
@@ -215,4 +215,7 @@
 
 int kvm_irqchip_add_msi_route(KVMState *s, MSIMessage msg);
 void kvm_irqchip_release_virq(KVMState *s, int virq);
+
+int kvm_irqchip_add_irqfd(KVMState *s, int fd, int virq);
+int kvm_irqchip_remove_irqfd(KVMState *s, int fd, int virq);
 #endif